Manual control for auxiliary brake device

ABSTRACT

An auxiliary brake device comprising a continuous flexible cable extending about a pair of sheaves secured to opposite ends of a vehicle axle, friction elements carried by the cable and engaging the sheave walls for braking the vehicle as the cable is drawn tight, a manual control means for optionally operating an automatic control to actuate the cable for applying the brake in the event of automatic control failure.

mte tates atet 1 9 Besoyan 1 Feb. 1, 1972 [54] MANUAL CONTRQL FORAUXILIARY 2,825,428 3/1958 Stiebinger ..188/162 BRAKE DEVICE 2,933,1594/1960 Stiebinger.. .....188/l06 P Inventor: Kirk y y Calif 3,516,5196/1970 Besoyan ..188/162 X [73] Assignee: Safety Vee Brake, Inc.,Blythe, Calif. Primary Examiner-Duane A. Reger [22] Filed: July 10 1970Attorney-Watson, Cole, Grindle & Watson [21] App]. No.: 53,795 [57]ABSTRACT An auxiliary brake device comprising a continuous flexible U-S-P, cable extanding about a pair of heaves ecured to opposite [51] Int.Cl ..Fl6d 65/34 ends of a vehicle axle friction eiemems carried by thecable [58] Flew 0f 106 106 162 and engaging the sheave walls for brakingthe vehicle as the cable is drawn tight, a manual control means foroptionally [56] References cued operating an automatic control toactuate the cable for apply- UNITED STATES PATENTS ing the brake in theevent of automatic control failure.

2,734,590 2/1956 Hays ..188/162 X 8 Claims, 6 Drawing Figures MANUALCONTROL FOR AUXILIARY BRAKE DEVICE This invention relates generally to avehicle braking device and, more particularly, to a means for manuallyapplying the brake of an auxiliary braking system which is otherwiseprovided with an automatically operable brake control.

In US. Pat. No. 3,5l6,5l9, issued June 23, I970 for an Auxiliary Brakeand Braking System and commonly owned by assignee herein, a brakemechanism or system is disclosed as one which is operable independentlyof a vehicle's ordinary service brakes and which is applicable fortrucks and other vehicles as an auxiliary piece of braking equipment.Such a brake is disclosed as comprising a flexible cable which extendsaround a sheave mounted at either end of the vehicle axle thereby actingas an auxiliary brake drum so that braking elements, which are carriedby the flexible cable, may be made to frictionally engage with the wallsof the sheave groove when the cable is drawn tight. The flexible cableis shown therein to extend about a pair of sheaves as a single cable sothat each end thereof may be automatically moved toward and away fromthe vehicle axle by means of a reversible motor operatively connectedthereto. Upon actuation of each electric motor, each end of the flexiblecable is thereby moved with relation to the vehicle axle so as to movethe cable either toward or away from the sheave groove therebyrespectively engaging and disengaging the friction elements with thesidewalls of the sheave groove. Although such a braking mechanism asdescribed therein is highly effective in stopping moving vehicles forwhich it is intended, certain areas of improvement have becomedesirable. For example, if one of the two electric motors becomesinoperable, the remaining operating motor would not only be placed underconsiderable strain during the braking of only one wheel, but thefriction elements and the cable associated with only one wheel would bepossibly not wholly effective in bringing the vehicle to a stop. Mostimportantly, in the event of a total electrical power failure of themotor vehicle, neither electric motor could obviously function to applythe auxiliary brake. Means have been accordingly devised foranticipating these potential difficulties and are made the subject ofthe present invention.

It is, therefore, the principle object of this invention to provide ameans for effectively braking a motor vehicle even in the event of anelectric power failure in the vehicle.

Another object of the present invention is to provide a control meanswhich will manually operate the auxiliary brake in the event that theautomatic brake control ceases to function.

A further object of this invention is to provide an auxiliary brakingdevice in which a plurality of friction elements are carried by aflexible cable extending about a sheave at each end of the vehicle axlewhich forms a brakedrum with which the friction elements make frictionalengagement when the cable is tightened, the means for tightening thecable being a reversible electric motor operatively associated with bothends of the cable through a meshing gear arrangement, and means formanually moving each cable and through the gear arrangement in the eventof failure by the motor.

A still further object of the present invention is to provide anauxiliary braking device as characterized wherein the gear arrangementincludes an elongated lever rod mounted at each end to one end of thecable so that upon rotation by either the motor or the manual controlthe rod will effectively tighten the cable about each sheave and brakethe vehicle axle.

A still further object of this invention is to provide such an auxiliarybraking device wherein the manual cable-moving means is a rotary shaftin constant engagement at one end with the electric motor gear andhaving provided at its other end a crank lever arm operativelyengageable for turning same.

Other objects, advantages and novel features of the invention willbecome apparent from the following detailed description of the inventionwhen considered in conjunction with the accompanying drawings, wherein:

FIG. I is a side view of a motor vehicle incorporating the improvedauxiliary braking device in accordance with the present invention;

FIG. 2 is a partial perspective showing one of a pair of rear dualwheels in relation to the auxiliary braking device of the presentinvention;

FIG. 3 is a sectional view taken along the line 33 of FIG. 2 showing aconventional brakedrum and brakeshoe arrangement for the vehicle;

FIG. 4 is a side view in elevation of the vehicle's rear wheel inrelation to the auxiliary braking device of the present invention;

FIG. 5 is a sectional view taken along the line 5-5 of FIG. 2 showingthe meshing gear arrangement of the brake device control; and

FIG. 6 is a view showing a crank arm mounted at an end of the manualcontrol shaft for rotating same.

Turning now to the drawings wherein like reference characters refer tolike and corresponding parts throughout the several views, there isshown in FIG. I, a motor vehicle I0 equipped with the auxiliary brakingdevice in accordance with the present invention which is shown moreclearly in FIG. 2 in its relation with the rear wheels of the vehicle.For the sake of clarity, only one of such wheels is shown at 11, therebeing normally a pair of dual wheels mounted at opposite ends of avehicle axle 12. The vehicle is equipped with a service brake in theform of a conventional brakedrum I4 at each axle end cooperable withconventional brakeshoes 13 as shown in FIG. 3. A sheave 15 similar tothe one described in the above-mentioned patent is mounted at each endof axle 12 onto the outer periphery of each brakedrum 14. A flexiblecable 16 extends about at least of the sheave circumference at each axleend so that each end 17 of the cable is located in a manner shown inFIG. 2, while the portion of the cable lying between sheaves extendsthrough an elongated tubular element 18 located transversely acrossvehicle frame members 21 and conveniently mounted thereto by means ofbrackets 19. As shown more clearly in FIGS. 4 and 5, the cable restsagainst a convex friction roller 22 mounted within each end of tubularelement 18 so that, upon movement of the cable ends 17, the portion ofthe cable extending through the tubular element will simply roll alongthe rollers. Tubular element 18 is slightly notched as at 23 (See FIG.2) to accommodate entry of the cable at opposite ends of the tubularelement.

A housing 24 for a meshing gear arrangement 25 is secured to element 18at approximately its centerline. The gear arrangement is provided forrotating an elongated lever rod 26 having a bevel gear 27 securedthereto in meshing engagement with a bevel gear pinion 28 mounted on ashaft 29 rotatable by means of a reversible electric motor 31. Oppositeends of elongated rod 26 are provided with a lever arm 32 secured at oneend as at 33 and having apertures 34 spaced longitudinally toaccommodate the cable end 17 in a preselected one thereof. Accordingly,upon energization of the electric motor 31, the elongated rod 26 isrotated through bevel gear and pinion 27, 28 so that lever arms 32 arepivoted about their ends 33 either toward or away from vehicle axle 12.Both ends 17 of the cable are moved so as to either tighten or loosenthe cable about each sheave by means of the reversible electric motor 31which serves as a single automatic control for the auxiliary brakedevice. As the cable is tightened about each sheave friction elements44, mounted on cable 16 in a manner similar to that described in thepreviously mentioned patent brought into frictional engagement with thesidewalls defining the groove of the sheave to thereby apply a brakingforce to the vehicle axle.

In the event of either a faulty motor 31 or a complete electric powerfailure of the vehicle, the bevel gear and pinion 27, 28 and hence themotor operated auxiliary brake device are rendered inoperable. A meansfor manually controlling the auxiliary brake is therefore available withthe present invention. Such a manual control is in the nature of arotatable shaft 35 operatively associated at one end with the meshinggear arrangement 25 and extending therefrom to the interior of thevehicle cab, as shown in FIG. I, in the vicinity of the driver's seat.The shaft 35 may be of any desired length to accommodate various sizedmotor vehicles and is conveniently secured to one of the frame members21 by means of brackets 36. Between these brackets, for example, theshaft may be a straight rigid rod and, between each bracket and theopposite ends of the shaft, it may be of the flexible rotary type whichis customarily designed as concentric, oppositely wound coil springs fortransmitting rotary motion along a curved line. The one end of shaft 35is provided with an external spur gear pinion 37 in meshing engagementwith an external spur gear 38 mounted on electric motor shaft 29. Theother end of shaft 35 is provided with a pair of short lugs 36 (only oneof which is shown in FIG. 6) for engagement with a portion of ahandcrank 41 which is provided with a forked collar member 42 having acoil spring 43 resting against the free end of shaft 35 to thereby urgethe handcrank away from such free end and out of engagement with lugs36. in this way, rotation of motor shaft 29 by the electric motor 31constantly rotates shaft 35 because of the spur gear and pinion 36, 37arrangement. This constant rotation of the shaft does not, however,interfere with the driver in the vehicle cab since the handcrank 42remains out of engagement with lugs 36 and the crank 41 thereforeremains stationary. If the electric motor 31 fails or if an electricalpower failure on the vehicle occurs, the manual control will be alwaysavailable for controlling the auxiliary brake system when the needarises. The driver simply depresses the crank 41 until the forked collarportion 42 engages with lugs 36 on shaft 35 whereafter the crank arm maythen be rotated for turning the spur gear and pinion 38, 37 which turnsthe bevel gear and pinion 2'7, 28 so as to rotate rod 26. Lever arms 32are then pivoted away from the vehicle axle so as to tighten the cableabout each sheave and thereby bring friction elements 44 into frictionalengagement with the sidewalls of the sheave groove. Naturally, a turn ofthe crank arm 41 in the opposite direction will cause lever arms 32 tobe pivoted toward the vehicle axle 12 and thereby loosen the cable aboutthe sheave whereupon the friction elements will become disengaged fromthe sidewalls of the groove sheave.

From the foregoing it can be seen that a simple and inexpensive, yethighly effective means for manually controlling an auxiliary brakesystem has been devised which is readily adaptable for use with thebrake system disclosed in the parent application. The driver simplyturns a crank which is conveniently located in the cab of the vehicle,and by his own muscle power in actuating the manual control system, maybring the vehicle to a complete stop if either the vehicle servicebrakes, the reversible electric motor or the entire electrical powersystem fails to operate. A runaway situation of the motor vehicle cantherefore always be avoided, first by application of the automaticallycontrolled auxiliary brake device and if this fails by application ofthe manual control system. The shaft 35 is always in direct operativeengagement with motor shaft 29 so that, when necessary, the motor shaftmay be rotated for tightening the cable 16.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is, therefore, tobe understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically described.

What is claimed is:

1. An auxiliary braking device for a vehicle having a frame, an axlecarried by said frame, a wheel at opposite ends of said axle,comprising, in combination, a sheave secured relative to and concentricwith each wheel for rotation therewith, a flexible cable extending aboutsaid sheaves over at least of each sheave circumference, said cablebeing movable toward and away from the bottom of the sheave groove, aplurality of friction elements carried solely by said cable into and outof frictional engagement with the sidewalls defining the groove of saidsheave, and means for moving said cable to draw the friction elementsinto and out of frictional engagement with said sheave groove sidewalls,said cable-moving means comprising a reversible electric motoroperatively associated with each end of said cable through a meshinggear arrangement for moving each cable end toward and away from saidvehicle axle and thereby moving said cable, and means for manuallymoving each cable end through said meshing gear arrangement in the eventof failure by said motor.

2. The auxiliary braking device according to claim 1, wherein saidmeshing gear arrangement comprises a plurality of intermeshing gearsoperatively associated with both said motor and an elongated lever rodfor rotating said rod which is interconnected at each end thereof with arespective cable end whereby, upon rotation of said rod, said cable endsare moved toward and away from said axle.

3. The auxiliary braking device according to claim 2, wherein saidmanuai cable moving means comprises a rotary shaft in meshing engagementat one end with one of said gears operatively associated with saidmotor, said shaft being rotatable during movement of said cable ends bymeans of said motor.

4. The auxiliary braking device according to claim 3, wherein the otherend of said shaft is provided with the crank arm operatively engageablewith said shaft.

5. The auxiliary braking device according to claim 4, wherein each saidend of said elongated lever rod is provided with a lever arm secured atone end thereto, each lever arm having longitudinally spaced aperturesand said cable ends being connected to the respective lever arms througha selected one of said apertures whereby, rotation of said shaft moveseach said arm about said secured end to thereby move each said cable endtoward and away from said vehicle axle.

6. The auxiliary braking device according to claim 4, wherein said shaftis of the flexible type along at least a portion of its length.

7. The auxiliary braking device according to claim 1, wherein saidvehicle has a conventional brakedrum and conventional brakeshoesassociated with each of said wheels for braking said vehicleindependently of the auxiliary braking device, each said sheave beingsecured to the outer periphery of each said drums.

8. The braking device according to claim 6, wherein said vehicle has aconventional brakedrum associated witheach of said wheels, each saidsheave being secured to the outer periphery of each said drums.

1. An auxiliary braking device for a vehicle having a frame, an axlecarried by said frame, a wheel at opposite ends of said axle,comprising, in combination, a sheave secured relative to and concentricwith each wheel for rotation therewith, a flexible cable extending aboutsaid sheaves over at least 180* of each sheave circumference, said cablebeing movable toward and away from the bottom of the sheave groove, aplurality of friction elements carried solely by said cable into and outof frictional engagement with the sidewalls defining the groove of saidsheave, and means for moving said cable to draw the friction elementsinto and out of frictional engagement with said sheave groove sidewalls,said cable-moving means comprising a reversible electric motoroperatively associated with each end of said cable through a meshinggear arrangement for moving each cable end toward and away from saidvehicle axle and thereby moving said cable, and means for manuallymoving each cable end through said meshing gear arrangement in the eventof failure by said motor.
 2. The auxiliary braking device according toclaim 1, wherein said meshing gear arrangement comprises a plurality ofintermeshing gears operatively associated with both said motor and anelongated lever rod for rotating said rod which is interconnected ateach end thereof with a respective cable end whereby, upon rotation ofsaid rod, said cable ends are moved toward and away from said axle. 3.The auxiliary braking device according to claim 2, wherein said manualcable moving means comprises a rotary shaft in meshing engagement at oneend with one of said gears operatively associated with said motor, saidshaft being rotatable during movement of said cable ends by means ofsaid motor.
 4. The auxiliary braking device according to claim 3,wherein the other end of said shaft is provided with the crank armoperatively engageable with said shaft.
 5. The auxiliary braking deviceaccording to claim 4, wherein each said end of said elongated lever rodis provided with a lever arm secured at one end thereto, each lever armhaving longitudinally spaced apertures and said cable ends beingconnected to the respective lever arms through a selected one of saidapertures whereby, rotation of said shaft moves each said arm about saidsecured end to thereby move each said cable end toward and away fromsaid vehicle axle.
 6. The auxiliary braking device according to claim 4,wherein said shaft is of the flexible type along at least a portion ofits length.
 7. The auxiliary braking device according to claim 1,wherein said vehicle has a conventional brakedrum and conventionalbrakeshoes associated with each of said wheels for braking said vehicleindependently of the auxiliary braking device, each said sheave beingsecured to the outer periphery of each said drums.
 8. The braking deviceaccording to claim 6, wherein said vehicle has a conventional brakedrumassociated with each of said wheels, each said sheave being secured tothe outer periphery of each said drums.